Camshaft, how hard to turn?

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Forrest - 19 Nov 2007 23:28 GMT

I have a 1989 Honda Accord SEI. It leaks oil and I have been letting my son
drive it. I have lectured him about checking it frequently but wonder if he
let it get too low. The engine quit on him as he was getting off of the
freeway. I towed him home and saw that I had no spark to the plugs. I took
the dist cap off and cranked it and the rotor didn't move. I removed the
valve cover and timing belt cover and cranked and could see the bottom
timing belt sprocket turning but not the top. I got the belt off and tried
to turn the top, camshaft sprocket by hand and it wouldn't move more than a
quarter of an inch. I figured that the cam shaft bearings may have frozen. I
loosened the bearing caps and I could then turn it. A guy at a wrecking yard
told me that it shouldn't have to be able to be turned by hand, but with a
wrench. How hard should it be to turn? I hate to spend $30 on a belt, put it
all back together, just to have it eat the new belt up. Thanks in advance
for any replies.

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motsco_ - 20 Nov 2007 03:46 GMT

> I have a 1989 Honda Accord SEI. It leaks oil and I have been letting my son
> drive it. I have lectured him about checking it frequently but wonder if he
[quoted text clipped - 10 lines]
> all back together, just to have it eat the new belt up. Thanks in advance
> for any replies.

----------------------------

Isn't the '89 an Interference Engine? If so, the sticky camshaft may be
only one of several problems. I don't remember how far back you have to
go to find a non-interference engine....

'Curly'

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jim beam - 20 Nov 2007 04:17 GMT

> I have a 1989 Honda Accord SEI. It leaks oil and I have been letting my son
> drive it. I have lectured him about checking it frequently but wonder if he
> let it get too low.

irrelevant.

> The engine quit on him as he was getting off of the
> freeway. I towed him home and saw that I had no spark to the plugs. I took
> the dist cap off and cranked it and the rotor didn't move.

timing belt has gone.

> I removed the
> valve cover and timing belt cover and cranked and could see the bottom
> timing belt sprocket turning but not the top.

see above.

> I got the belt off and tried
> to turn the top, camshaft sprocket by hand and it wouldn't move more than a
> quarter of an inch.

use a wrench. it's held by powerful springs.

> I figured that the cam shaft bearings may have frozen. I
> loosened the bearing caps and I could then turn it.

that's because you loosen the springs.

> A guy at a wrecking yard
> told me that it shouldn't have to be able to be turned by hand, but with a
> wrench. How hard should it be to turn? I hate to spend $30 on a belt, put it
> all back together, just to have it eat the new belt up. Thanks in advance
> for any replies.

now you've loosened the caps, you've broken the plug tube seals and need
to get new ones. you can remove completely to check the bearings, but
unless the motor's been run dry, or run with the belt excessively tight,
they'll be fine. tip: remove the whole assembly, with bolts in place,
as one unit and keep it all together. reassembly once it falls apart
can be a pita.

other than that, you need to see if any valves are bent from the belt
breakage. re-tighten the bearings and check for valve lash. if any are
excessive, valves are bent and the head needs to come off for
replacement. based on what you've said so far, i suggest you then hand
the vehicle to someone with the experience to take the job from there.

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Forrest - 20 Nov 2007 20:10 GMT

>> I have a 1989 Honda Accord SEI. It leaks oil and I have been letting my
>> son drive it. I have lectured him about checking it frequently but wonder
[quoted text clipped - 30 lines]
> now you've loosened the caps, you've broken the plug tube seals and need
> to get new ones.

you can remove completely to check the bearings, but

> unless the motor's been run dry, or run with the belt excessively tight,
> they'll be fine. tip: remove the whole assembly, with bolts in place, as
[quoted text clipped - 6 lines]
> based on what you've said so far, i suggest you then hand the vehicle to
> someone with the experience to take the job from there.

Jim Beam wrote:

"now you've loosened the caps, you've broken the plug tube seals and need
to get new ones."

I don't know what those are. Could you please elaborate on that point? Sure
I can't just align it all, re-torque the caps and put on the new belt?

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Tegger - 20 Nov 2007 23:54 GMT

> jim beam wrote:
>
[quoted text clipped - 5 lines]
> Sure I can't just align it all, re-torque the caps and put on the new
> belt?

jim is referring to Honda's sytem of SOHC head design. There are O-rings
that keep oil out of the spark plug holes. You may not be able to get those
to seal again without replacing them. Big job!
http://www.tegger.com/hondafaq/oilyplugs/index.html

1) Depending on how careful you were when loosening the bearing caps, you
may or may not have distorted the camshaft. This would require camshaft
replacement.

2) The valves may be bent, preventing free rotation of the engine. That's a
head-off job to fix, and very expensive.

At this point I'd say the quickest way to find out what you've got is to
retighten the bearing caps, pull the pistons all down to half-way, then
turn the camshaft so you can check all the valve clearances. If you have
one or more that are wildly large, that valve's bent.

Signature

Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

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